Balance.



PATENTED' SEPT. 1, 1908.

J. NELSON. BALANCE. APPL IGATION FILED OCT. 27, 1906.

3 SHEETS-SHEET 1.

PATENTBD SEPT. 1, 1908.

J. NELSON. BALANCE. APPLICATION FILED OUT. 27, 1906.

3 SHEETS-SHEET 2.

PATENTBD SEPT. 1, 1908.

J. NELSON.

BALANCE.

APPLICATION FILED OCT. 27. 1900.

3 SHEBTSSHEET 3.

mmms PETERS co., wnsumarau, n c.

noon NELSON, or

CHICAGO, ILLINOIS, ASSIGNOR TO EDWARD P. MARTIN COMPANY, OF

CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.

BALANCE.

Specification of Letters Patent.

Patented Sept. 1, 1908.

Application filed October 27, 1906. Serial No. 340,823.

To all whom it may concern:

Be it known that I, J ACOB NELSON, a citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Balances, of which the following is a specification.

The object of this invention is the general improvement of the Jolly balance, with a view to increased facility and accuracy in operation and the enlargement of its scope of usefulness in the laboratory.

One of the features of the invention is the provision of convenient means for accurately making readings.

Another feature is an improved means for quickly adjusting the position of the table or stage;

The invention also relates to an improved spiral spring having no tendency to twist during elongation.

The invention further refers to the other improvements in balances hereinafter set forth.

In the accompanying drawings, Figure 1 is a side elevation of a balance embodying the features of my invention. Fig. 2 is a fragmental side elevation of the balance, the standard being shown in vertical central section. Fig. 3 is a fragmental detail view of the standard and the slidably mounted sleeve that supports the table. Fig. 4 is a sectional view taken on the plane of dotted line 4 4 of Fig. 1. Fig. 5 is a detail view of the feed nut and the sleeve upon which it is carried. Fig. 6 is a sectional view on dotted line 6 6 of Fig. 2. Fig. 7 is a section, on an enlarged scale, taken on the plane of line 7 7 of Fig. 2. Fig. 8 is a section on line 8 of Fig. 2. Fig. 9 is a sectional view on dotted line 9 9 of Fig. 2. Fig. 10 illustrates an alternative means for 'operatively connecting the crank shaft and the feed screw.

The embodiment herein shown of my invention comprises a tripod base 1 to which a gear case 2 is secured by means of a pin 3 fixed with relation to said gear case, said pin extending through an opening 4 in the tripod base and having a clamping nut 5 turned upon its screw-threaded end. The tripod base 1 is provided with leveling screws 6. On the upper side of the gear case 2 is a tubular neck 7 which is made resilient or compressible by forming a plurality of slits 8 therein. This neck receives the lower end of the tubular standard 9, the latter being adjustably secured in said neck by means of a clamp ring 10 surrounding said neck and pro-. vided with a screw 11 for clamping said neck and standard together. In the tubular standard 9 is rotatably supported a feed screw 12 having fixed to its lower end a bevel oinion 13 adapted to mesh with a similar pinion 14 fixed upon a crank shaft 15 rotatably mounted in the gear case 2. Upon one end of the shaft 15 is fixed a crank 16 for rotating the feed screw 12. It is obvious that the shaft 15 and the feed screw 12 may be'operatively connected in various ways. In Fig. 10 I have shown a construction wherein flexible 'shafting 17 is substituted for the pinions 13 and 14.

Upon the tubular standard 9 is slidably mounted a sleeve 18 having a guide rib 19 which lies within a slot 20 formed in the walls of said standard. The sleeve 18 has fixed thereto two rings 21 through which the feed screw 12 extends. A half-nut 22 is slidably mounted between guides 23 formed upon the sleeve 18, said half-nut being connected by means of the links 24 with one arm of a lever 25 pivotally mounted upon the sleeve 18. The other arm of said lever is provided with a finger portion 26. A curved leaf spring 27 fixed at one end to the last mentioned arm of the lever 25 and bearing at its other end against the adjacent portion of the sleeve 18 tends to hold the half-nut 22 in engagement with the feed screw 12. A tubular stud 28 fixed with relation to the sleeve 18 receives the stem 29 of the table or stage 30, said table being clamped in position by means of the set screw 31.

In the upper end of the tubular standard 9 is slidably mounted a rod 32 adapted to be fixed with relation to said standard by means of a set screw 33. To the upper end of the rod 32 is secured a cross arm 34 having a vertical opening 35 through its outer end to receive the attaching portion 36 of the spring 37, said attaching portion being secured in said opening by means of the set screw 38. The spring 37 is formed of fine spring wire coiled for one-half of its length in one direction, and throughout the rest of its length in the opposite direction, as indicated in Fig. 1. This construction eliminates the tendency, present in springs wound throughout their length in the same direction, toward axial movement or twisting when the standard 9 by spring is elongated. To the lower end of the spring 37 is attached a link 39 bent at its up per end to form a loop 40, the lower portion of said link being similarly bent, but to the opposite side of the vertical axis of the link, for the purpose of making the link symmetrical. To the lower end of the link 39 is hung a scale pan 41, commonly of metal, and from the lower side of said pan is suspended a second scale pan 42, usually of glass.

A contact blade 43 is. provided with a securing stem 44 extending through a perforated stud 45 upon the sleeve 18, said. stem being adjustably secured with relation to said sleeve by means oi a set screw 46. The stem 44, in this instance, is .not of integral construction, but consists of two sections connected together, but insulated from each other, by means of the insulating section 47. The contact blade 43 is adapted to extend into the loop 40 of the link 39, said link being provided. with a platinum contact pin 48 arranged to contact said blade. The latter is electrically connected. by means of the insulated. wire 49 with a contact 50 upon an insulating block 51 fastened. to the tripod base, said contact being arranged to be electrically connected with a binding post by means oi the switch arm 53. WVhcn the balance is in. use said binding post 52 is connected. by means of a wire 54 (Fig. 4) with one pole of a battery 55, the opposite pole of said battery being connected with a binding post 56 upon the insulating block 51 by a wire 57. A bell or other electrically-actuated signaling device 58 is included in the circuit at any convenient point.

The standard 9 is graduated in millimeters, as indicated in Figs. 1 and 3. Upon the sleeve 18 is fixed a scale portion 59 having thereon a space of nine millimeters divided into ten equal portions, thus forming a vernier permitting the making of readings to one-tenth of a millimeter.

To illustrate the operation of this balance, we will suppose that it be desirable to ascertain the specific gravity of, say, a solid heavier than and insoluble in water. The solid is placed in the upper scale pan 41, the rec 32 being raised or lowered, as required, so that the solid shall be suspended at a convenient point for the weighing operation. The sleeve 18 is then adjusted upon the manually moving the same up or down, the operator withdrawing the hall nut 22 from engagement with the feed screw 12 by means of the lever 25 until the contact blade 43 is brought within the loop 40 of the link 39. The sleeve 18 is then further adjusted by slowly rotating the crank 16 until the contact blade 43 is moved into contact with the platinum contact pin 48. As soon as such contact is established an electric cir- ;cu.it is closed through the battery 55 and the signaling device 58, causing the operation of said device. The point at which contact between the blade 43 and the pin 48 is established can be more accurately determined in this way than by means of the eye. WVhen the point of contact between the blade 43 and the pin 48 has thus been ascertained, a reading is taken. The solid is then placed in the lower an 42, the latter being submerged in water in a tumbler, beaker or other suitable vessel set upon the table 30. The contact blade 43 is then adjusted as before, the coarse adjustment being obtained by manually moving the sleeve 18 and the liner adjustment by rotating the crank 16, until the contact blade 43 is caused to contact with' the platinum pin 48, when the circuit is again closed and the signaling device operated. The lower pan 42, of course, is kept submerged to the same depth throughout the experiment. A secondreading is then taken and the specific gravity determined. from the two readings. In this instance the object in forming the spring 37 so that the tendency to rotation of the spring during elongation is eliminated, is to prevent the loop 40 or any other part ol the link 39 'lrom being rotated into contact with the contact plate 43 or its securing stem 44, as would occur in the use 01' the ordinary coiled spring. (.ontact between the plate 43 or the stem 44 and the link 3.) would, of course, interfere with the making of close measurements.

This apparatus may be used in the performance of a variety of experiments. The link 39, pans 41 and 42, table 30, and contact blade 43 may be readily removed when neces sary.

While I have hereinbefore described the present embodiment of my invention with some particularity, I recognize the fact that various changes may be made in the construction and arrangement of the parts of said embodiment, therefore, no undue limitation should be understood from the foregoing detailed description.

The means herein shown for making accurate readings, to wit, a signaling device in cluded in an electric circuit arranged to be closed by the movement of the part used for making the readings, obviously may be employed in various forms of scales, barometers and other apparatus by means of which measurements are made. Other features, also, of this balance may be adapted for use in measuring instruments of various types.

I claim as my invention:

1. In a measuring instrument, in combination, a base ,a gear case secured to said. base; a tubular standard secured to said gear case; a scale; an indicator on said standard; a feed screw in said standard for moving said indicator a shaft rotatably mounted in said. gear case, said shaft being connected with said feed screw ,and means for rotating said shaft.

2. A link for Jolly balances adapted to be detachably secured at one end to a spring and at the other to a scale pan, said link having a loop therein and a contact member fixed to said link within said loop.

3. In a balance, in combination, a spring; a scale pan; a link for connecting said spring and said scale pan, said link having a loop therein; a contact point attached to said link; an indicator; and a contact member fixed to said indicator adapted to enter said loop and contact with said contact point.

4. In a balance, in combination, a base; a gear case secured to said base, said gear case having a tubular, compressible neck; a standard adapted to fit within saidneck; a clamp ring surrounding said neck; and a screw for tightening said clamp ring.

5. In a measuring instrument, in combination, a standard; a feed screw; a member slidably mounted on said standard, said member having guides thereon; a half-nut slidably mounted between said guides; a lever pivotally mounted on said sleeve; a link connecting said half-nut and said lever; and a spring tending to move said lever in one direction.

6. In a Jolly balance, in combination, a tubular standard; a rod adjustably fixed in the upper portion of said standard, said rod carrying means for supporting a spring; 'a feed screw rotatably mounted in said standard; means for rotating said screw; a sleeve slidably mounted on said standard and carrying means adapted to engage said feed screw; a table and an indicator carried by said sleeve; and a scale on said standard.

7. In a Jolly balance, in combination, a base; a tubular standard secured thereto in vertical position, said standard having an elongated longitudinal slot therein; a feed screw rotatably mounted in said standard; means for rotating said screw; a sleeve slidably mounted on said standard and having a guide rib arranged to lie within said slot; means carried by said sleeve adapted to extend through said slot into engagement with said feed screw; a table and an indicator carried by said sleeve; and a scale on said standard.

8. In a balance, in combination, a scale pan; a contact point arranged to move with said scale pan; a scale; an indicatorfor said scale; a contact point movable with said indicator; a signaling device; an electric circuit including said contact points and said signaling device; and a coiled spring connected with and supporting said scale pan, one-half of said spring being coiled in one direction and one-half in the opposite direction.

JACOB NELSON. 

